Solving Simple Equations Part 1

1
Solving Simple Equations Part 1

• September 4, 2008
• Essential Question
• Solve c 4.85 2 ¼

2
Expressions vs. Equations

• Expressions
• 4x 7
• 9 y

• Equations
• 4x 7 10
• 9 y 3

Whats the difference?
3
Solving Equations

• A solution of a variable equation is a number
  that you can substitute for a variable to make
  the equation true.
• This means that you are finding all the answers
  for this problem!

4
Ways to solve equations!

• 1st Option
• Mental Math
• Some equations will be very easy to just look at
  and solve.

5
Examples of Mental Math

• 8 x 3
• 11 7 y
• 7w 63
• d 5 40

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Ways to solve equations!

• 2nd Option
• Inverse Operations
• Not all problems will be
• as easy to see the
• answers
• Fractions
• Decimals
• Negative s

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Inverse Operations

• What are inverse operations?
• They are mathematical operations that undo
• another operation
• Examples

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Steps to using inverse operations

• ?
• X 7.5 23.1
• - 7.5 - 7.5
• _____________
• X 15.6

• Find the number on the same side of the equal
  sign with your variable.
• Look at the sign in front of that number, and use
  the inverse operation on both sides of the equal
  sign.
• Simplify

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Examples of solving

• y 5 -3

• 19 z 18

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Word Problems

• A divers equipment weighs 30 pounds. The diver
  and the equipment
• weigh 160 pounds. How much does the diver weigh?